Mold for casting forged material, and method for casting forged material

Abstract

The invention is directed to a method for casting a forged material and a mold usable therefor. A finished metal product which is free from the internal defects is manufactured by solidifying a forged material in a specified direction, with concentrating the defects in the riser portion of the mold for casting a forged material. The finished metal product having a lightweight is produced with a less cost, resultantly, carbon dioxide discharged from the automobiles is reduced, thereby the present invention can contribute to environmental protection measures such as preventing global warming.

Description

BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT[0001] The present invention relates to a mold for casting a forged material, and a method for casting a forged material, both of which are usable for casting a molten forged material. More particularly, the present invention relates to a mold for casting a forged material usable for manufacturing a metal product produced via forging process, such as, for example, a vehicle suspension part for an automobile or the like, and is capable of casting a forged material having poor castability so as to prevent an internal defect, and a method for casting a forged material using the mold.[0002] The reduction in fuel consumption of an automobile is required on a global scale to prevent global warming that is one of global environmental problems. To reduce the fuel consumption, weight reduction techniques of an automobile are considered to be the most significant. It is because an automobile having lightened weight can reduce a load on a po...

AI Technical Summary

Problems solved by technology

The cast products have merit in the point that they are easy to manufacture, but there is a limit in improvement of the mechanical strength thereof.

Thus, it is difficult to use the cast products for automobile parts such as suspension parts that are required to be less corrosive, have a sufficient strength and a good extending property, and have fewer defects, and that significantly relate to safety.

However, the forged products or the squeeze cast products have a problem to be solved of high cost, and applications thereof are extremely limited at present.

The reason why a conventional aluminum forged product wherein A6061 alloy or the like is used, and is preferably employed as the suspension part for the automobile is high in cost is mainly that the forged material per se is high in cost, and also that it requires a large number of manufacturing steps.

Further, for example, since a squeeze cast product using an AC4CH alloy requires a large number of manufacturing steps and is low in injection speed, the cost reduction thereof can not be attained due to the low productivity.

On the other hand, it is clear that the application of general cast products to the suspension part used in hostile environments is difficult, even if one devotes oneself to reduce the occurrence of defects by cleaning a molten metal.

That is, only 70% of the material are used for a forged product, and this brings a big waste.

If a supplier is required to provide a material having a shape similar to a shape of a product to be produced in order to minimize the amount of unnecessary burrs to forging, the manufacture of such a material having a particular and non-standard shape by forging, even if possible, would bring too significant increase in cost for the manufacturers to afford it only by restraining the amount of burrs to be produced.

To produce a material having the shape similar to the shape of the product by forging would lower a forging ratio, and disturb the improvement in mechanical properties.

This would result in losing the superiority of the forging process, and thus remain the problem unsolved.

However, the property required for a material to be forged is plasticity or toughness as described above, and the molten metal of the forged material has poor fluidity or a poor solidification shrinkage property relating to casting ability.

Thus, casting defects such as a shrinkage cavity are observed when it is cast and molded, and mechanical properties of a metal product obtained thereafter by forging are deteriorated.

Consequently, since the products are not stable in the quality, it is difficult to use machining scrap such as the burrs for a raw material for the forged metal product having good mechanical properties and higher quality, even if the scrap is originally a forged material.

However, there have been proposed no appropriate metal product for such a use.

Images